Art of cooking.



A. c. Mmmm.

'ABT or COOKING.

APPLICATION FILED APBM, 1911.

Patentad Aug.29,1911.

AUSTIN C. DUNHAM, OF EARTEOFD, CONNECTECUT.

ART .GF CUGKNG.

Specification of Letters Patent.

)Patented ning. 2Q, 19ML.

Application filed April 14, 1911.. Serial No. 621,088.

To all whom 'it may concern:

y Be it known that l, AUSTIN C. lDUNHAM, I

- current for light and power purposes can, profitably to itself,furnish means for cooking food at such `very low rate as to bring itscost within the reach of people in modest nancial circumstances.

i. To accomplish this object the cost of the apparatus, the cost ofinstalling it, and, more especially, the cost of the operating current,must be so lo-W that it will meet the competition of apparatus utilizingcoal, oil or gas as fuel, otherwise it will not be Within the reach ofthe consumer oflim-ited means. ln order to effect this lat a prolit `tothe produc-ing company, .the apparatus must be simple to manufacture,and the conditions of use must be such that the current can be suppliedWithout necessitating an increase of the generating and distributingequipment of the central station. It is well known that a centralstation must have hpparatus sufficient to sup-ply current to meet themaximum demand or'the peak of the load.7 The peak4 of the load .comes atvarious times under different conditions, for instance, in a systemdevoted solely 4to lighting, the load is heaviest during the eveninghours. The remainder of the twenty-four hours of the day the load islight. ln a power plant the peak occurs during the working hours of theday, while with a plant furnishing-current for both light and power thepeak is reachedduring' the short period when motors and lamps are bothbeing used at the same time. A compa-ny can supply current profitably,at a low rate to `the consumer, if the demand is uniform and is extendedthroughout the twenty-four hours of the day, for this raises the.so-called average load line or tends toward the theoretical conditionof economy, which is what is known as the hundred per cent. load factorstriven for by central stations. ln other words, if .a demand is spreadover twenty-four hours, the increased income derived from the many hoursof lowdemand more than makes up for `the additional cost of the increaseat the short time of the peak.

Certain degrees of heat are desirable to satisfactorily cook food.. litis a self eVident fact that if the required degree of temperature isonce obtained, it is only nec-essary to supply the heat lost byabsorption and radiation in order" to maintain that tem-- perature.duced to practically nothing, the amount of energy necessary to maintaina specific degree of temperature once obtained will be very small.Consequently, in carrying out this invention a simple oven chamber isconstructed in such manner that, at the desired internal cookingtemperature, the loss of heat by radiation is very slight, in factpractically nothing. rlhis chamber is provided with simple mea-ns whichmerely supplies enough heat to compensate for 'the loss due to externalradiation and the absorption by the food to be cooked. This slightamount of heat necessary to keep the temperature uniform is developed bya small quantity of electric current, but in order to accomplish thisresult with the low current factor, the current is supplied continuouslyfor twenty-four hours, thus keeping the temperature uniform andeliminating the lf the loss by radiation is re-y necessity of extraamounts of current that A would be necessary if the chamber were allowedto cool .olf and which probably would be Wanted at the time of heaviestdemand on the system. This equalizes the load on the operating plant,and it is only in this manner that the central station company, withprofit to itself, can furnish current for cooking at sufficiently lowrates to bring it within the purchasing power of consumers of limitedmeans.

This invention has been developed to meet the requirements of a centralstation, and

the a paratus illustrated in the accompanying rau/ings has been usedfoi-'some time for bakin roasting and boiling foods'V in order todemonstrate the practicability of this invention.

Figure 1 shows a front elevation of such an ap aratus. Fin. 2 shows avertical section o the same. llig. 3 shows a horizontal section. Fig. eshows a plan on larger form current of electricity of less'than 150 betreated in, and silibjecting them to the Watts.. z

`G. The method of constantly maintaining has heet non-conducting wallsand which is the interior of it heat insulated cooking provided with anelectrical heating resistchanber at a .uniform erii'cient cookingtemance of small capacity through which there peinture, whichconsistsindeveloping heat is a continuous flow of electricl current oftherein by continuously-v passing there- 10W Wattage. through anniformelectric currentof 10W AUSTIN C. DUNHAM. Wattage. 1

7. The treatment of foodv substances which consists in placing thesubstances t0 Witnesses:

RALPH D. CUTLER, H. R-` WILLIAMS.

Copies of thispatent may be ebtained for lfive `cents each, byaddressing the Commissioner of Patents,

. i Washington, D. G.

uniform temperature of, :i chamber which.

